Invited Talk: Promises, Lies, and Dry-Run Mode

The speaker will deliver a presentation, which will be followed by group discussion.

Speaker: Sean O'Meara, Opscode

The world became addicted to dry-run mode when it was introduced with the make utility. Convergent policy–based CM systems are a completely different animal. The best you can hope to do in a dry-run scenario is to evaluate listed promises against the current state of the system. However, during a real-world run, operators change the underlying system, their side effects determining the behavior of operations down the line. I suspect the ability of a dry-run output to follow a linear line: A 99% configured system's dry-run output can be mostly trusted, whereas a 0% configured system's dry-run output is made up of lies and failure.

Discuss.